Touch of silk to repair ruptured eardrums

A transparent, silk-derived implant that looks like a contact lens and can fix damaged eardrums is giving hope to millions who suffer from recurrent ear infections.

Creators of the device—from the Australian Research Council’s Future Fibres Research Hub and the Perth-based Ear Science Institute Australia (ESIA)—secured funding to start human clinical trials with it in Australia in 2018.

The implant, called ClearDrum, is made from silk protein that forms a see-through scaffold on which cells can grow to close eardrum perforations.

Surgeries to repair eardrums often use a patient’s cartilage from the outer ear, which is shaped into a membrane that blocks the perforation. This acts as the middle ear’s barrier against infection.

Operations can be lengthy and require repeat procedures. But the new device will enable quicker, less invasive surgeries and offer a ‘window’ into the middle ear to assess healing and potential infection. It is super-thin, strong, flexible, biodegradable and unlikely to cause rejection.

“Even if you use the strongest cartilage, it’s opaque so surgeons can’t see through it into the middle ear. The silk implant provides comparable strength with transparency and vibrates as well as a human eardrum,” says Deakin University’s Dr Rangam Rajkhowa.

Up to 330 million people worldwide suffer from middle ear disease, which can damage eardrums. About 10 per cent of indigenous Australian children under the age of 14 experience chronic burst eardrums from infection. This can lead to hearing loss and learning and employment difficulties.

The team, led by Hub Director Professor Xungai Wang, won a three-year grant of just under four million dollars from UK-based charity The Wellcome Trust.

Dr Rangam Rajkhowa preparing silk eardrum scaffolds for testing. Credit: Deakin UniversityThe implant is clear so surgeons can see through into the middle ear. Credit: Deakin University